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asp.net-mvc - 如何在 ASP.NET MVC 中使用复选框创建选择列表?

转载 作者:行者123 更新时间:2023-12-02 14:49:46 24 4
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我有一个数据库表,记录允许用户访问哪些出版物。该表非常简单 - 它仅存储用户 ID/出版物 ID 对:

CREATE TABLE UserPublication (UserId INTEGER, PublicationID INTEGER)

给定用户和出版物的记录的存在意味着该用户具有访问权限;没有记录意味着无法访问。

我想向我的管理员用户展示一个简单的屏幕,允许他们配置用户可以访问哪些出版物。我想为每一种可能的出版物显示一个复选框,并检查用户当前可以访问的出版物。然后,管理员用户可以选中或取消选中任意数量的出版物并提交表单。

出版物类型有多种,我想将类似类型的出版物分组在一起 - 因此我确实需要控制出版物的呈现方式(我不想只有一个平面列表)。

我的 View 模型显然需要有一个所有出版物的列表(因为我需要显示所有出版物,无论当前选择如何),并且我还需要用户当前有权访问的出版物的列表。 (我不确定使用单个列表是否会更好,其中每个项目都包含出版物 ID 和是/否字段?)。

但这就是我所能得到的。我真的不知道如何将其绑定(bind)到某些复选框。我从哪里开始?

最佳答案

针对您的问题的 Linq to SQL 模型如下所示:

alt text

首先,我们的数据模型中需要一些辅助对象:

namespace SelectProject.Models
{
public class UserPublicationSelector
{
public int UserPublicationID { get; set; }
public int UserID { get; set; }
public int PublicationID { get; set; }
public string PublicationName { get; set; }
public bool IsSelected { get; set; }
}

public class UserPublicationSelectViewModel
{
public User User { get; set; }
public IQueryable Selections { get; set; }
}
}

现在让我们创建一个如下所示的存储库:

public class Repository
{
DataContext dc = new DataContext();

public User GetUser(int userID)
{
return dc.Users.FirstOrDefault(u => u.UserID == userID);
}

public IQueryable GetUserPublications(int userID)
{
return from p in dc.Publications
join up in dc.UserPublications on p.PublicationID equals up.PublicationID
where up.UserID == userID
orderby p.PublicationName
select p;
}
public IQueryable GetUserPublicationSelectors(int userID)
{
return from p in dc.Publications
join up in dc.UserPublications on p.PublicationID equals up.PublicationID into selected
from s in selected.DefaultIfEmpty()
orderby p.PublicationName
select new UserPublicationSelector
{
UserPublicationID = (int?)s.UserPublicationID ?? 0,
UserID = userID,
PublicationID = p.PublicationID,
PublicationName = p.PublicationName,
IsSelected = s.UserID != null
};
}

public void UpdateUserPublications(UserPublicationSelector[] selections)
{
// Insert records for new selections...
foreach (UserPublicationSelector selection in selections.Where(s => s.IsSelected == true))
{
// ...where records do not yet exist in database.
if (selection.UserPublicationID == 0)
{
UserPublication up = new UserPublication
{
UserID = selection.UserID,
PublicationID = selection.PublicationID,
};
dc.UserPublications.InsertOnSubmit(up);
}
}
// Delete records for unselected items...
foreach (UserPublicationSelector selection in selections.Where(s => s.IsSelected == false))
{
// ...where record exists in database.
if (selection.UserPublicationID > 0)
{
UserPublication up = dc.UserPublications.FirstOrDefault(s => s.UserPublicationID == selection.UserPublicationID);
if (up.UserID == selection.UserID && up.PublicationID == selection.PublicationID)
dc.UserPublications.DeleteOnSubmit(up);
}
}
// Update the database
dc.SubmitChanges();
}
}

还有一个 Controller ,如下所示:

public class PublicationController : Controller
{
Repository repository = new Repository();

public ActionResult Index(int id)
{
User user = repository.GetUser(id);
var publications = repository.GetUserPublications(id);
ViewData["UserName"] = user.UserName;
ViewData["UserID"] = user.UserID;
return View("Index", publications);
}

[AcceptVerbs(HttpVerbs.Get)]
public ActionResult Select(int id)
{
var viewModel = new UserPublicationSelectViewModel()
{
User = repository.GetUser(id),
Selections = repository.GetUserPublicationSelectors(id)
};
return View("Select", viewModel);
}

[AcceptVerbs(HttpVerbs.Post)]
public ActionResult Select(int userID, UserPublicationSelector[] selections)
{
repository.UpdateUserPublications(selections);
return RedirectToAction("Index", new { id = userID });
}
}

索引 View 如下所示:

<%@ Page Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<IEnumerable<Publication>>" %>
<%@ Import Namespace="SelectProject.Models" %>

<asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server">
List of Selected Publications for User
</asp:Content>

<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">

<h2>Publications for <%= ViewData["UserName"] %></h2>

<table id="MyTable" style="width: 100%">
<thead>
<tr>
<th>
Publication Name
</th>
</tr>
</thead>

<tbody>
<% int i = 0;
foreach (Publication item in Model)
{ %>

<tr id="row<%= i.ToString() %>">
<td>
<%= Html.Encode(item.PublicationName)%>
</td>
</tr>

<% i++;
} %>
</tbody>
</table>
<p>
<%= Html.ActionLink("Edit Selections", "Select", new { id = ViewData["UserID"] })%>
</p>

</asp:Content>

选择 View 如下所示:

<%@ Page Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<UserPublicationSelectViewModel>" %>
<%@ Import Namespace="SelectProject.Models" %>

<asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server">
Select Publications
</asp:Content>

<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">

<h2>Select Publications for <%= Model.User.UserName %></h2>

<% using (Html.BeginForm())
{ %>

<table id="MyTable" style="width: 100%">
<thead>
<tr>
<th style="width: 50px; text-align:center">
<input type="checkbox" id="SelectAll" />
</th>
<th>
Publication Name
</th>
</tr>
</thead>

<tbody>
<% int i = 0;
foreach (UserPublicationSelector item in Model.Selections)
{ %>

<tr id="row<%= i.ToString() %>">
<td align="center" style="padding: 0 0 0 0">
<%= Html.CheckBox("selections[" + i.ToString() + "].IsSelected", item.IsSelected)%>
<%= Html.Hidden("selections[" + i.ToString() + "].UserPublicationID", item.UserPublicationID)%>
<%= Html.Hidden("selections[" + i.ToString() + "].UserID", Model.User.UserID)%>
<%= Html.Hidden("selections[" + i.ToString() + "].PublicationID", item.PublicationID)%>
</td>
<td>
<%= Html.Encode(item.PublicationName)%>
</td>
</tr>

<% i++;
} %>
</tbody>
</table>
<p>
<%= Html.Hidden("userID", Model.User.UserID) %>
<input type="submit" value="save" />
</p>

<% } // End Form %>

<script src="../../Scripts/jquery-1.4.1.js" type="text/javascript"></script>

<script type="text/javascript">
// Select All Checkboxes
$(document).ready(function() {
$('#SelectAll').click(function() {
var newValue = this.checked;
$('input:checkbox').not('input:hidden').each(function() {
this.checked = newValue;
});
});
});
</script>

</asp:Content>

这里有一些屏幕截图。

alt text

alt text

左上角的复选框是一个全选/全选复选框。

关于asp.net-mvc - 如何在 ASP.NET MVC 中使用复选框创建选择列表?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/2531052/

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